Refinishing Cypress Exterior Doors

In this area of the country they use a lot of cypress in home building. It is not unusual to find kitchen cabinets made out of cypress and also exterior doors. Also not unusual in this area is a lot of sunlight, heat, and humidity. All have an effect on wood.It the photos there are two sets of doors, mine and my neighbors. My doors I refinished three years ago, and my neighbors last week. I remove the doors and cover the opening with OSB sheathing. The process I use is to remove the hardware, the raised panels, and sand the exterior to bare wood. The interior I sand to remove any imperfections, but not to bare wood. The panels are split to the point of being broken at the joint lines and some cracks go all the way through and almost the length of the panel. I break them apart, joint them if necessary and glue them back together. Then I sand both sides to bare wood and refinish them outside the doors.The interior of the doors I apply three coats of Polyurethane sanding between each with 220 grit and before the last coat 0000 steel wool.The exterior I start with a 50/50 mix of spar urethane and paint thinner and sand with 180 and then 220 grit sandpaper. Then I apply five coats of spar urethane sanding between each coat with 220 grit and before the last again with 0000 steel wool.I follow the same method for the door frame sanding the face down to bare wood and applying spar urethane on the outside and polyurethane interior.The finish on the doors is beautiful although it is a time consuming process that takes approximately two weeks.